将用户实例的表单填写限制为每天一次(Django)

from django.db import models
from django.contrib.auth.models import User

class UserProfile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    last_submission = models.DateTimeField(null=True, blank=True)

from django import forms
from django.utils import timezone

class MyForm(forms.Form):
    # 表单字段定义

    def clean(self):
        cleaned_data = super().clean()
        user = self.request.user  # 获取当前用户
        last_submission = user.userprofile.last_submission

        if last_submission and last_submission.date() == timezone.now().date():
            raise forms.ValidationError("每天只能填写一次表单")

        return cleaned_data

from django.shortcuts import render
from .forms import MyForm

def my_view(request):
    if request.method == 'POST':
        form = MyForm(request.POST)
        if form.is_valid():
            # 处理表单数据
            form.save()

            # 保存用户最后填写时间
            user = request.user
            user.userprofile.last_submission = timezone.now()
            user.userprofile.save()

            return render(request, 'success.html')
    else:
        form = MyForm()

    return render(request, 'form.html', {'form': form})